Various types of filling apparatus are known in the art. In one common use, such an apparatus is used to fill containers with a flowable product, such as milk, juice and the like. As will be recognized by those skilled in the art, such a flowable product can be liquid, dried, granulated or powered products, as well as a combination of such solid (e.g., dried, granulated or powdered) and liquid materials.
Those skilled in the art will recognize that filling must be done in a controlled, metered manner in order to assure that the proper quantity in weight or volume is added to each container. Moreover, in order to prevent spilling or splashing of the flowable product, a controlled, and controllable, end of the filling cycle is desirable. It has been observed that when the end of the filling cycle is controlled, the final amount of product in the container is more readily controlled and filling the container with the desired amount can be achieved.
A typical filling apparatus includes a tank or reservoir for storage of the flowable product, such as storage of milk. One or more filling trains receive milk from the storage tank and pump the milk into respective containers through a filling valve and nozzle arrangement.
Various types of valves are known in the art. One type of valve that is commonly used at the apparatus discharge to the container is referred to as an "umbrella valve". The umbrella valve includes a body having a generally round fluid passage therethrough contiguous with an expanding, conical-shaped valve opening. A valve plug has a conical-shaped plug body that is complementary to the valve opening. A valve stem extends from the top of the conical plug, through the fluid passage. The valve plug is actuated by, for example, a mechanical actuator or a pneumatic cylinder operably connected to the stem to move the plug between the opened and closed positions.
The umbrella valve is so-called because of the flow profile of the fluid exiting the valve. That is, when fluid flows through a passage formed between the conical-shaped plug and body, it exits the valve and flows in a paraboloid shape, much like water flowing off of an umbrella.
One drawback to the umbrella valve arrangement that has been observed is that there is often spraying of the liquid from the passage between the body and plug. This is due to a large pressure drop at the umbrella valve plug edge with resulting fluid spray. It will, of course, be recognized that such a spray is undesirable, in that it can fall onto the outside of the container and the surfaces of the filling apparatus. In addition, such spraying can cause foaming of the product as it is filling the container, which is also an undesired effect.
Accordingly, there continues to be a need for an umbrella valve arrangement, in which the flow of material through the valve is controlled, resulting in a more controlled and predictable umbrella-like flow profile, and a controllable end of filling flow profile.